National Aeronautics and Space Administration
Orbital Debris Quarterly News Volume 11, Issue 3 July 2007 UN Committee Accepts Space Debris Mitigation Guidelines Inside... In February 2007 the Scientific and Technical uses of outer space, to devise programs in this field Subcommittee (STSC) of the United Nations’ to be undertaken under the auspices of the United Investigation of MMOD Committee on the Peaceful Uses of Outer Space Nations, to encourage continued research and Impact on STS-115 (COPUOS) completed a multi-year work plan with the dissemination of information on outer space Shuttle Payload the adoption of a consensus set of space debris matters, and to study legal problems arising from mitigation guidelines (Orbital Debris Quarterly the exploration of outer space. The membership of Bay Door��������������������2 News, 11-2, p.1). The full COPUOS, at its latest COPUOS now includes 67 Member States. meeting in Vienna, Austria, during 6-15 June, has The STSC will continue to include space debris Optical Observations also accepted these guidelines. as an agenda item for its annual meetings. Beginning of GEO Debris with COPUOS was established by the United in 2008 Member States are encouraged to report Two Telescopes ���������6 Nations General Assembly in 1959 to review the their progress in implementing the new UN space scope of international cooperation in the peaceful debris mitigation guidelines. ♦ Optical Measurement Center Status �������������7
Disposal of Spacecraft Detection of Debris from Chinese ASAT Test and Launch Vehicle Increases; One Minor Fragmentation Event Stages in LEO ������������8
GEO Population in Second Quarter of 2007 Estimates Using The extent of the debris cloud created by the increase of fragmentation debris in Earth orbit of Optical Survey destruction of the Fengyun-1C meteorological an estimated 75% (Figure 1). Data �����������������������������9 satellite on 11 January 2007 by a Chinese ballistic The Fengyun-1C debris cloud extends from interceptor is becoming more apparent as routine 200 km to 4000 km in altitude, with the highest Space Missions and and special radar observations of the fragments continued on page provide more data. By the Orbital Box Score ����10 7000 end of June 2007 the U.S. Space Surveillance Network 6000 (SSN) was tracking more than 2200 objects with a size 5000 of at least 5 cm. 4000 More than 1900 of
these debris had been 3000 officially cataloged, making the event by far the worst 2000 satellite fragmentation of the space age. The Chinese 1000
anti-satellite (ASAT) test 0 7 9 1 3 5 7 9 1 3 5 7 9 1 3 5 7 9 1 3 5 7 9 1 3 5 7 5 5 6 6 6 6 6 7 7 7 7 7 8 8 8 8 8 9 9 9 9 9 0 0 0 0
A publication of 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 0 0 0 0 coupled with other satellite 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 Year The NASA Orbital breakups in the first quarter of the year has resulted in an Figure 1. The total number of known fragmentation debris in Earth orbit increased by Debris Program Office about 75% during the first quarter of 2007. Orbital Debris Quarterly News
Detection of Debris continued from page 1
of only one or a few debris with very small 31405), and it is likely to have also separated separation velocities. The debris appear to from Vanguard 3 in 2006, possibly about the “fall-off” their parent satellites, probably due time of the first piece. The newly discovered to environmental degradation or small particle debris is decaying at a slower pace than the impacts (Johnson, 2004). debris seen last year, but both are falling back In April a new piece (U.S. Satellite to Earth much faster than Vanguard 3 from its Number 31408) from the derelict U.S. Seasat orbit of 500 km by 3300 km. spacecraft (International Designator 1978- 064A, U.S. Satellite Number 10967) was 1. Johnson, N.L., “Environmentally-Induced detected. This was the 15th debris from Seasat Debris Sources”, Advances in Space Research, cataloged since 1983 and the fourth seen Vol. 34 (2004), Issue 5, pp. 993-999. ♦ during the past four years (Figure 3). These debris exhibit a variety of ballistic coefficients, Figure 2. The debris cloud from the Fengyun-1C spacecraft is rapidly dispersing. but all decay relatively rapidly compared to Seasat itself, which is in a stable, nearly circular concentration near the breakup altitude of orbit near 750 km. Additional debris have approximately 850 km. The debris orbits are been briefly detected rapidly spreading (Figure 2) and will essentially from Seasat, but they encircle the globe by the end of the year. Only have reentered prior 101 a few known debris had reentered more than to being cataloged. Seasat five months after the test, and the majority will The source of the 100 27889 31408 remain in orbit for many decades. debris could be 99 The large number of debris from either the spacecraft 28843 98 Fengyun-1C are posing greater collision or the Agena upper 28143 )
risks for spacecraft operating in low Earth stage to which it is n i 97 m orbit. The number of close approaches has still attached. ( d o
i 96 risen significantly. On 22 June, NASA’s Terra Early in 2006 r e spacecraft had to execute a collision avoidance an anomalous event P 95 maneuver to evade a fragment from Fengyun- involving the 46- 1C that was on a trajectory which would have year-old Vanguard 3 94 passed within 19 meters of Terra. was detected (Orbital After a flurry of satellite breakups in Debris Quarterly 93 the first quarter of 2007, the next three months News, 10-3, p. 2). 92 witnessed only one minor fragmentation A second piece has 2003 2004 2005 2006 2007 classified as an anomalous event. An anomalous now been cataloged event is normally characterized by the release (U.S. Satellite Number Figure 3. A new piece of debris separated from the Seasat spacecraft in early 2007. PROJECT REVIEWS Investigation of MMOD Impact on sts-115 Shuttle Payload Bay Door Radiator J. Hyde, E. Christiansen, D. Lear, J. 2024-T81 facesheets Kerr, F. Lyons, J. Yasensky and Al5056-H39 cores. The face- 1. Introduction sheets are topped The Orbiter radiator system consists of with 0.005 in. eight individual 4.6 m x 3.2 m panels located (0.127 mm) silver- with four on each payload bay door. Forward Teflon tape. The panels #1 and #2 are 2.3 cm thick while the radiators are located aft panels #3 and #4 have a smaller overall on the inside of thickness of 1.3 cm. The honeycomb radiator the shuttle payload panels consist of 0.028 cm thick Aluminum continued on page Figure 1 Cross section of orbiter radiator facesheet. www.orbitaldebris.jsc.nasa.gov
MMOD Impact continued from page 2 bay doors, which are closed during ascent and observations revealed reentry, limiting damage to the on-orbit portion exit damage on the of the mission. rear facesheet. Impact Through crack of damage features on the inner face sheet 2. Post Flight Inspection rear facesheet included Post-flight inspections at the Kennedy Space a 0.03 in. diameter hole Center (KSC) following the STS-115 mission (0.76 mm), a ~0.05 in. Crack length, 0.267” revealed a large micrometeoroid/orbital debris tall bulge (~1.3 mm), (MMOD) impact near the hinge line on the and a larger ~0.2 in. tall #4 starboard payload bay door radiator panel. bulge (~5.1 mm) that FWD The features of this impact make it the largest exhibited a crack over ever recorded on an orbiter payload bay door 0.27 in. (6.8 mm) long. radiator. The general location of the damage A large ~1 in. (25 mm) site and the adjacent radiator panels can be seen diameter region of the in Figure 2. Initial measurements of the defect honeycomb core was Hole, 0.031” indicated that the hole in the facesheet was also damaged. Refer to 0.108 in. (2.74 mm) in diameter. Figure 3 shows Figure 4 for an image All measurements ± 0.005” an image of the front side damage. Subsequent of the backside damage continued on page Figure 4. Rear facesheet damage on starboard radiator #4.
0.4in (10.2mm) IMPACT LOCATION
Panel 4 Hinge Line
Panel 3 0.85in (21.6mm)
Panel 2
Panel 1
1.1in (27.9mm)
Figure 2. Orbiter payload bay door radiators (starboard panels 1-4 shown).
Figure 5. Front facesheet with thermal tape removed. Extent of damaged facesheet is hghlighted.
Figure 6. SEM images of hole in front facesheet. Asymmetric nature of lip can be Figure 3. Front facesheet damage on starboard radiator #4. seen in the oblique view. Orbital Debris Quarterly News
MMOD Impact continued from page 3
entry hole in the facesheet. The asymmetric height of the lip may be attributed to projectile shape and impact angle. Numerous instances of a glass-fiber organic matrix composite were observed in the facesheet tape sample. The fibers were approximately 10 micrometers in diameter and variable lengths. EDS analysis indicated a composition of Mg, Ca, Al, Si, and O. Figures 7 and 8 present images of the fiber bundles, which were believed to be circuit board material based on similarity in fiber diameter, orientation, consistency, and composition.
4. Hypervelocity Impact Tests A test program was initiated in an attempt to simulate the observed damage to the radiator facesheet and honeycomb. Twelve test shots Figure 7. Example SEM image and EDS spectra of circuit board fragment. were performed using projectiles cut from a continued on page 5
HITF07017: tape delamination STS-115 RH4: tape delamination dimensions = 11.2mm x 10.2mm dimensions = 13.1mm x 12.1mm
5mm 5mm
Figure 8. SEM image of circuit board fragment. Figure 9. Entry hole in upper facesheet. to the panel. No damage was found on thermal Exit Hole blankets or payload bay door structure under Max the radiator panel. Figure 5 shows the front facesheet with the thermal tape removed. Ultrasound examination Exit Hole indicated a maximum facesheet debond extent Min of approximately 1 in. (25 mm) from the entry hole. X-ray examinations revealed damage to an estimated 31 honeycomb cells with an extent of 0.85 in. x 1.1 in. (21.6 x 27.9 mm).
3. SEM/EDS Analysis Pieces of the radiator at and surrounding 5mm 5mm the impact site were recovered during the repair procedures at KSC. They included the thermal tape, front facesheet, honeycomb core, and rear 2nd damage site facesheet. These articles were examined at JSC HITF07017: rear facesheet damage STS-115 RH4: rear facesheet damage using a scanning electron microscope (SEM) dimensions = 3.3mm x 0.4mm dimensions = 0.8mm hole, 6.8mm crack with an energy dispersive x-ray spectrometer (EDS). Figure 6 shows SEM images of the Figure 10. Exit hole in lower facesheet. www.orbitaldebris.jsc.nasa.gov
MMOD Impact continued from page 4
1.6 mm thick fiberglass circuit board substrate a typical ISS mission. There is a 0.4% chance Table 1. MMOD impact risk for a typical shuttle panel. Results from test HITF07017, shown in (impact odds = 1 in 260) that a 1.25 mm or mission to ISS from particles 1.25 mm and larger. figures 9 and 10, correlates with the observed larger MMOD particle would impact the RCC Odds of Region MMOD Impact Risk impact features reasonably well. The test was wing leading edge and nose cap during a typical Impact performed at 4.14 km/sec with an impact angle mission. Figure 11 illustrates the vulnerable of 45 degrees using a cylindrical projectile areas of the wing leading edge reinforced Upper TPS 7% 1 in 15 with a diameter and length of 1.25 mm. The carbon-carbon (RCC), an area of the vehicle fiberglass circuit board material had a density that is very sensitive to impact damage. The Lower TPS 1.7% 1 in 59 of 1.65 g/cm3, giving a projectile mass of highlighted red, orange, yellow, and light green 2.53 mg. areas would be expected to experience critical Radiators 1.6% 1 in 62 damage if impacted by an OD particle such
5. Impact Risk as the one that hit the RH4 radiator panel on Wing Leading Edge 0.4% 1 in 260 An analysis was performed using the STS-115. ♦ and Nose Cap RCC Bumper code to estimate the probability of impact to the shuttle from a 1.25 mm diameter Windows 0.04% 1 in 2500 particle. Table 1 shows a 1.6% chance (impact odds = 1 in 62) of a 1.25 mm or larger MMOD Total Vehicle 10% 1 in 10 impact on the radiators of the vehicle during
RCC areas vulnerable to the OD particle* that perforated STS-115 radiator RH4.
Critical Orbital Debris Ø Failure Criteria (7km/s & 0°) 1.00” Ø hole 4.89mm 0.71 m2 0.50” Ø hole 2.75mm 0.18 m2 0.25” Ø hole 1.68mm 0.52 m2 0.10” - 0.99” Ø hole 1.10-4.84mm 2 1.52 m 0.25” Ø exposed substrate (Test 6) 0.81mm 0.19” Ø exposed substrate (Test 11) 0.69mm 0.14” Ø exposed substrate (Test 5) 0.58mm 0.09” Ø exposed substrate (Test 4) 0.47mm
12.07 m2 19.09 m2 2.53 m2 * OD particle properties: 1.13 m2 type = glass (or ceramic) fiber composite diameter = 1.0 – 1.2mm 2 0.54 m assumed impact angle = 45° 0.34 m2 assumed impact velocity = 4km/sec
Figure 11. MMOD Failure Criteria for RCC: wing leading edge, nose cap and chin panel.. Orbital Debris Quarterly News
Optical Observations of GEO Debris with Two Telescopes P. Seitzer, K. Abercromby, H. Rodriguez, and E. Barker 12 For several years, the Michigan Orbital DEbris Survey Telescope (MODEST), the University of Michigan’s 0.6/0.9-m Schmidt 10 telescope on Cerro Tololo Inter-American Observatory in Chile has been used to survey the debris population at GEO in the visible 8 n i
regime. Magnitudes, positions, and angular b r rates are determined for GEO objects as they e p
r 6 move across the telescope’s field-of-view (FOV) e b during a 5-minute window. m u This short window of time is not long N enough to determine a full six parameter 4 orbit so usually a circular orbit is assumed. A longer arc of time is necessary to determine 2 eccentricity and to look for changes in the orbit with time. MODEST can follow objects in real- time, but only at the price of stopping survey 0 operations. A second telescope would allow 0.001 0.005 0.01 0.05 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 for longer arcs of orbit to obtain the full ECC six orbital parameters, as well as assess the changes over time. An additional benefit of Figure 1. The histogram of all objects (32) for which enough data exists to determine a full six-parameter orbit having a second telescope is the capability of without the a circular orbit assumption. obtaining BVRI colors of the faint targets, aiding efforts to determine the material type of faint debris. 0.80 For 14 nights in March 2007, two telescopes were used simultaneously to observe the GEO 0.70 debris field. MODEST was used exclusively in survey mode. As objects were detected, they 0.60 were handed off in near real-time to the 0.50 y
Cerro Tololo 0.9-m telescope for follow-up t i c i r observations. The goal was to determine orbits t th n 0.40 e
and colors for all objects fainter than R = 15 c c magnitude (corresponds to 1 meter in size E 0.30 assuming a 0.2 albedo) detected by MODEST. The hand-off process was completely functional 0.20 during the final eight nights and follow-ups for objects from night-to-night were possible. 0.10 The cutoff magnitude level of 15th was selected on the basis of an abrupt change in 0.00 the observed angular rate distribution in the 12 13 14 15 16 17 18 th MODEST surveys. Objects brighter than 15 Magnitude (R) magnitude tend to lie on a well defined locus in the angular rate plane (and have orbits Figure 2. Eccentricity versus magnitude for each of the 32 objects for which a full six-parameter orbit was in the catalog), while fainter objects fill the calculated. plane almost uniformly. We need to determine the 0.9-m telescope (only 0.22°, compared circular orbits, but 20% of the objects had full six-parameter orbits to investigate what with 1.3° for MODEST). The average time from eccentricities greater than 0.2. Figure 2 depicts causes this change in observed angular rates. last detection on MODEST to first detection eccentricity versus magnitude and Figure 3 Are these faint objects either the same on the 0.9-m telescope was 17 minutes; the shows inclination versus right ascension of population of high area-to-mass (A/M) objects quickest was 4 minutes. Thus, the statistical ascending node (RAAN) for the same set of on eccentric orbits as discovered by the ESA completeness of the follow-up sample is very objects. Space Debris Telescope (Schildknecht, et al. high. The ability to run two telescopes 2004), or are they just normal debris from Figure 1 shows a histogram of the 32 simultaneously provides a very powerful probe breakups in GEO? objects for which enough data was collected of the GEO debris field. Initial observations Our success rate in handing off was greater to determine the full orbit parameters. indicate that we are seeing both a circular and than 85%, despite the very small FOV of The majority of the objects were in continued on page www.orbitaldebris.jsc.nasa.gov
Optical Observations 18 continued from page 6 16 an eccentric debris populations. We look forward to continuing these observations in the 14 future. Our next run is planned for November s
2007. e 12 e r
1. Schildknecht, et al., Properties of the High g e
d 10
Area-to-mass Ratio Space Debris Population , n o in GEO, AMOS Technical Conference i t
a 8
Proceedings, Kihei, Hawaii, pp. 216-224, n i l c
September 2-5, 2005. ♦ n I 6
4 Visit the NASA Orbital Debris 2 Program Office 0 Web Site 0 50 100 150 200 250 300 350 www.orbitaldebris.jsc.nasa.gov RAAN, degrees Figure 3. Inclination versus RAAN for each of the 32 objects in this specific dataset. Optical Measurement Center Status
H. RODRIGUEZ, K. ABERCROMBY, M. rise to interesting photometric light curves. DARCON or Nomex netting with aluminized MULROONEY, AND E. BARKER In addition, filter photometry was conducted Mylar for the middle layers. This material is Beginning in 2005, an optical measurement on the MLI pieces, a process that also will be significant to the study of space debris due to center (OMC) was created to measure the used on the ESOC2 samples. While obtaining its high area-to-mass ratio (A/M) and the effect photometric signatures of debris pieces. light curve data an anomalous drop in intensity solar radiation pressure perturbations have on Initially, the OMC was equipped with a 300 was observed when the table revolved through its orbital evolution. Measurements were taken W xenon arc lamp, a SBIG 512 x 512 ST8X the second 180 degree rotation. Investigation at an 18 degree phase angle with one intact MEI CCD camera with standard Johnson revealed that the robot’s wrist rotation is not piece and three different layers of MLI, using filters, and a Lynx 6 robotic arm with five reliable past 80 degrees, thus the object may the standard astronomical filters mentioned degrees of freedom1. As research progressed, be at slightly different angles at the 180 degree previously. The A/M ratios range from 8 to modifications were made to the equipment. A transition. To limit this effect, the initial rotation 43 m2/kg (3 m2/kg and greater is considered customized rotary table was built to overcome position begins with the object’s minimal to be a high A/M). In Figure 1, a digital image the robot’s limitation of 180 degree wrist surface area facing the camera. of two pieces of MLI layering is displayed. rotation and provide complete 360 degree The top left and right images are part of the rotation with little human interaction. This outermost layer of MLI. The copper-colored change allowed an initial phase angle (source- Kapton is space-facing, while the silver color object-camera angle) of roughly 5 degrees to borders the interior MLI layers. The bottom be adjusted to 7, 10, 15, 18, 20, 25, or 28 degrees. left and right images are part of the spacecraft- Additionally, the Johnson R and I CCD filters facing MLI layer, with the copper-color Kapton were replaced with the standard astronomical facing the spacecraft while the silver color is filters suite (Bessell R, I). In an effort to reduce positioned to the interior MLI layers. object saturation, the two generic aperture stops The following figure shows an example of were replaced with neutral density filters. intensity versus rotation over 360 degrees for Initially data were taken with aluminum the intact piece of MLI (see Figure 2). The debris pieces from the European Space pseudo-debris piece was rotated through five Operations Centre ESOC2 ground test and degree increments at a seven degree phase more recently with samples from a thermal Figure 1. Digital Images of sample MLI debris. Top angle. Filter photometry data was taken through images are part of the space-facing layer and the multi-layered insulation (MLI) commonly used bottom images are part of the space-craft facing all five filters mentioned previously. The two on rocket bodies and satellites. The ESOC2 layer. The A/M for these samples is ~ 10 m2/kg. intensity maxima around 90 and 270 degrees data provided light curve analysis for one correspond to the maximum surface area of type of material but many different shapes, The MLI used for the current study the object facing the CCD camera. The object including flat, bent, curled, folded, and torn2. consists of space-facing copper-colored was rotated space-craft side first, then space- The MLI samples are roughly the same size Kapton with an aluminized backing for the facing side during the remaining 180 degrees and shape, but have different surfaces that give top and bottom layers and alternating layers of continued on page 8 Orbital Debris Quarterly News
OMC Status continued from page 7 of rotation. The structure in the light curve is due to the surface structure of the object — where the space-craft facing layer is more uniform in composition, while the space- facing layer has a mesh structure on the edges and a perforated flat surface in the middle. If one were to compare the light curve of MLI to a flat plate rotated at the same phase angle over a 360 rotation, one would see that the flat plate would also show a bimodal plot, but a with a smoothed plot exhibiting a sinusoidal character In addition to photometric laboratory measurements, laboratory spectral measurements will be taken with the same MLI samples. Spectral data will be combined to match the wavelength region of photometric data so that a fiduciary reference can be established for the photometric measurements. Spectral data of MLI shows a strong absorption feature near 4800 Angstroms, which is due to the copper color of Kapton. Space debris containing MLI may therefore Figure 2. Intensity versus Rotation through five filters: Clear, Bessell R, Bessell I, Johnson B, and Johnson V. be identified via telescopic observations employing either high resolution spectroscopy by illustrating the optical properties expected orbital space environment. or narrow-band photometry. Furthermore, we for a high A/M object. will ascertain whether the absorption feature Future work will involve more complex 1. rodriguez, H.M., Abercromby, K. J., is sufficiently broad to enable identification rotations for different pieces of pseudo-debris Jarvis, K. S., and Barker, E., Orbital Debris via broad-band (R-B) photometry. and will incorporate other phase angles. An Photometric Study, ODQN, Vol. 10, Issue 2. Using laboratory photometric and spectral optical mirror is available for configuring measurements, an optical property database the OMC for a 90 degree phase angle. The 2. rodriguez, H.M., Abercromby, K. J., Jarvis, will be provided for an object with a high ongoing research is aimed towards developing K. S., and Barker, E., Using Light Curves A/M made of similar materials to MLI. The an optical Size Estimation Model (SEM) to Characterize Size and Shape of Pseudo- benefits of this database for remote optical comparable to the current radar SEM so Debris, 2006 AMOS Technical Conference, measurements of orbital debris will be shown that a better model may be obtained for the Maui, Hawaii, 10-14 September 2006. ♦ abstractS from the nasa orbital debris program office Second International Association for the Advancement of Space Safety (IAASS) Conference 14-16 May 2007, Chicago, Illinois, USA The Disposal of Spacecraft and Launch Vehicle Stages in Low Earth Orbit
N. JOHNSON resulting in the creation of large numbers of altitude of the vehicle, achieving the goal of As a result of the increasing number of new orbital debris. Likewise, the passivation orbital lifetime reduction can influence the debris in low Earth orbit (LEO), numerous of these objects, i.e., the removal of residual design and deployment philosophy of a new national and international orbital debris stored energies, while they remain in orbit is space system. Some spacecraft and launch mitigation guidelines recommend the removal important to prevent the generation of debris vehicle stages have combined their end-of- of spacecraft and launch vehicle stages from via self-induced explosions. Characteristics and mission passivation operations with maneuvers LEO within 25 years after mission termination. trends in the growth of the derelict spacecraft to vacate long-lived orbital regimes. Perhaps The primary purpose of this action is to and launch vehicle stage populations in LEO the most dramatic demonstration of this type enhance space safety by significantly limiting are examined. occurred in 2006 when a U.S. Delta IV second the potential of future accidental collisions Depending upon the final operational continued on page 9 www.orbitaldebris.jsc.nasa.gov
The Disposal of Spacecraft continued from page 8 stage executed an unprecedented controlled- to be imposed. debris mitigation measures, although highly reentry maneuver from a circular orbit at an The most important passivation measures recommended, is not yet sufficiently practiced altitude near 850 km. For space systems in for a spacecraft or launch vehicle stage are (1) due to the design of the current generation orbital regimes near the upper regions of LEO the removal (normally by burning or venting) of spacecraft and launch vehicles or due to (i.e., between 1400 km and 2000 km altitude), of residual propellants and pressurants and other influences. Spacecraft with no maneuver maneuvers to place the vehicle above LEO (2) the electrical discharge of batteries and, if capability and solid-propellant upper stages might be more attractive than attempting to applicable, their disconnection from charging can pose serious challenges to compliance with ensure an atmospheric reentry within 25 years, circuits. Several examples of how a number of disposal recommendations. As a class, small and at least one space system operator has countries and international organizations have satellites, especially mini-, micro-, and pico- selected this option. In some cases, careful already been working to responsibly dispose satellites, often fall short in their adherence to consideration of natural orbital perturbations of LEO spacecraft and launch vehicle stages orbital debris mitigation guidelines. However, can also lead to reduced orbital lifetimes, are presented. efforts are underway to identify cost-effective although new launch constraints might need On the other hand, the adoption of such solutions. ♦ 2007 Space Control Conference 1-3 May 2007, MIT Lincoln Laboratory, Lexington, Massachusetts, USA GEO Population Estimates Using Optical Survey Data E. BARKER, M. MATNEY and magnitude distributions of these fainter unstable for this population and thus difficult Optical survey data taken using the NASA debris objects are markedly different from the to predict. Their dim visual magnitudes and Michigan Orbital Debris Survey Telescope catalogued population. photometric variability make observations a (MODEST) gives us an opportunity to GEO debris consists of at least two challenge. The IADC has enlisted a series statistically sample faint object population in different populations, one which follows the of observatories (participating institutions: the Geosynchronous (GEO) and near-GEO standard breakup power law and one which has University of Michigan/CTIO, Astronomical environment. This paper will summarize the anomalously high Area-to-Mass Ratios (1 to Institute University of Bern, Boeing LTS/ MODEST survey work that has been conducted ~30 m2/kg; a sheet of paper = ~13 m2/kg). AMOS, Keldysh Institute of Applied by NASA since 2002, and will outline the The Inter-Agency Space Debris Mathematics) at different longitudes. Complete techniques employed to arrive at the current Coordination Committee (IADC) is investigating observational coverage over periods of days to population estimates in the GEO environment objects in GEO orbits with anomalously high months will provide a better understanding of for dim objects difficult to detect and track Area-to-Mass Ratios (AMRs). The ESA Space the properties, such as solar radiation pressure using current systems in the Space Surveillance Debris Telescope discovered this population effects on orbital elements, size, shape, attitude, Network (SSN). and defined its general properties [inclinations color variations, and spectral characteristics. Some types of orbits have a higher detection (0 to 30 degrees), changing eccentricities (0 and Results from recent observational programs rate based on what parts of the GEO belt are 0.6), and mean motions (~1 rev)]. The accepted will be summarized, and includes a description being observed; a straightforward statistical interpretation of this orbital behavior is that of the orbit elements prediction processes, a technique is used to debias these observations solar radiation pressure drives the perturbations summary of the metric tracking performance, to arrive at an estimate of the total population causing time dependent inclinations and and some photometric characteristics of this potentially visible to the telescope. The size eccentricities. The orbital parameters are class of debris.
UPCOMING MEETINGS
10-14 September 2007: 2007 Advanced 23-27 September 2007: Hypervelocity 24-28 September 2007: The 58th Maui Optical and Space (AMOS) Impact Symposium (HVIS), Wiliamsburg, International Astronautical Congress, Surveillance Technologies Conference, Virginia, USA. Hyderabad, India. Wailea, Maui, Hawaii, USA. This biennial symposium is dedicated A Space Debris Symposium is planned The 2007 AMOS Conference will cover to enabling and promoting an understanding for the congress. The three scheduled various topics in adaptive optics, astronomy, of the basic physics of high velocity impact sessions will address the complete spectrum imaging, lasers, metrics, non-resolved object and related technical areas, including of technical issues of space debris, including characterization, orbital debris, Pan-STARRS, spacecraft shielding design and orbital measurements and space surveillance, SSA programs and systems, and telescopes debris environment. More information can modeling, risk assessment, reentry, hyper- and sensors. Additional information on be obtained at http://hvis.org/HVIS_07/ velocity impacts, protection, mitigation, and the conference is available at http://www. index.html. standards. Additional information on the amostech.com. Congress is available at http://www.iac2007. org.
INTERNATIONAL SPACE MISSIONS ORBITAL BOX SCORE (as of 20 SEP 2006, as cataloged by July - 24 September 2006 US SPACE SURVEILLANCE NETWORK)
Earth Rocket Other Country/ International Country/ Perigee Apogee Inclination Orbital Payloads Bodies Total Payloads Cataloged Organization Designator Organization (KM) (KM) (DEG) Rocket & Debris Debris Bodies CHINA 54 322 376 NAVSTAR 58 2006-042A USA 20014 20349 55.0 2 0 (USA 190) CIS 1360 2865 4225 2006-043A DIRECTV 9S USA 35775 35798 0.0 1 1 ESA 36 36 72
2006-043B OPTUS D1 AUSTRALIA 35772 35802 0.0 FRANCE 44 309 353 INDIA 31 108 139 2006-043C LDREX 2 JAPAN 261 35568 7.0 JAPAN 96 85 181 2006-044A METOP-A ESA 820 821 98.7 1 0 US new1028 data to3038 come 4066 2006-045A PROGRESS-M 58 RUSSIA 325 357 51.6 OTHER 360 28 388
2006-046A SJ-6C CHINA 594 599 97.7 1 3 TOTAL 3009 6791 9800 2006-046B SJ-6D CHINA 598 600 97.7
2006-047A STEREO A USA HELIOCENTRIC 1 1 Technical Editor 2006-047B STEREO B USA HELIOCENTRIC J.-C. Liou
2006-048A SINOSAT 2 CHINA EN ROUTE TO GEO 1 0 Managing Editor Debi Shoots 2006-049A XM-4 USA 35783 35790 0.1 1 0 Correspondence concerning the 2006-050A DMSP 5D-3 F17 USA 840 856 98.8 1 66 ODQN can be sent to: 2006-051A ARABSAT 4B RUSSIA 35763 35809 0.0 1 1 Debi Shoots NAVSTAR 59 NASA Johnson Space Center 2006-052A USA 20205 20367 55.1 2 0 (USA 192) Orbital Debris Program Office 2006-053A FENGYUN 2D CHINA 35782 35789 2.6 2 0 Mail Code JE104 Houston, TX 77058 2006-054A WILDBLUE 1 newFRANCE data35780 to come35794 0.0 1 1 [email protected] 2006-054B AMC-18 FRANCE 35784 35790 0.0
2006-055A STS 116 USA 314 339 51.6 0 3
2006-055B MEPSI USA 308 328 51.6
2006-055C RAFT USA 312 331 51.6 MEETING REPORT 2006-055D MARSCOM USA 312 332 51.6 The second conference of the recently
2006-055F ANDE SPHERE 1 USA 313 336 51.6 established International Association for the Advancement of Space Safety (IAASS) was held 2006-055J ANDE SPHERE 2 USA 312 336 51.6 in Chicago during 14-16 May. Sessions on orbital debris hazards and reentry risks spanned a day and 2006-056A MEASAT-3 MALAYSIA 35774 35798 0.1 1 1 a half of the conference, including topics on the 2006-057A USA 193 USA NO ELEMS. AVAILABLE 1 0 disposal of spacecraft and rocket bodies in low Earth orbit, nuclear reactor coolant droplets in 2006-058A TACSAT 2 USA 412 424 40.0 1 0 long-lived orbits, protection of space vehicles from 2006-058C GENESAT USA 412 424 40.0 micrometeoroid and orbital debris particles, and reaction wheel designs to minimize reentry risks. 2006-059A ETS 8 (KIKU 8) JAPAN EN ROUTE TO GEO 1 0 A new committee on space debris is being formed 2006-060A SAR LUPE 1 GERMANY 468 505 98.2 1 0 under the IAASS. The next conference of the IAASS will be held in Rome during 21-23 October 2006-061A MERIDIAN 1 RUSSIA 1031 39752 98.2 1 0 2008. ♦ 2006-062A COSMOS 2424 RUSSIA 19078 19134 64.8 2 1
2006-062B COSMOS 2425 RUSSIA 19138 19155 64.8
National Aeronautics and Space Administration
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